A. Field of the Invention
The present invention is related to connecting rods for railway brake riggings, extending beneath the bolster for transferring a force to the braking mechanism, and more particularly to a connecting rod in which it's linking means are joined at each end by means of a pressure fit joint.
B. Description of the Related Art
In a typical railway freight car, an air cylinder is connected by an assortment of levers and rods to brake beams associated with each pair of wheels. In many cases, a connecting rod extends beneath the bolster of the railway truck connecting both brake beams by means of a lever system.
Most connecting rods actually in use are completely casted in a single piece, which makes them very heavy and difficult to handle. Other connecting rods are comprised by a hollow steel pipe, and have its linking means either welded to each end of the hollow steel pipe or joined by any other known means, which reduce the strength of the connecting rod.
In view of the above referred problem, applicant developed a connecting rod in which it's linking means are joined at each end by means of a pressure fit joint.
The connecting rod of the present invention comprises a hollow steel pipe having a first and a second open end and linking means inserted at each open end of the hollow steel pipe and joined thereof by means of a pressure fit joint.
Each linking means has a cylindrical shaped coupling section having a specific profile forming a peripheral bump section and at least one annular groove so that each cylindrical shaped coupling section is inserted in a correspondent open end until the edge of each open end bumps against said peripheral bump section, and the walls thereof conforms to the profile of the correspondent cylindrical receiving section, thus retaining the correspondent linking means.
The connecting rod of the present invention is a low cost alternative to common connecting rods for mechanical rigging systems, since the linking means are joined to the ends of the hollow bar by means of a pressure fit joint, without the need of adding further materials or welding both elements and without the need of casting a single piece which is very common in the art.
Furthermore, the connecting rod of the present invention is lighter and stronger than a casted connecting rod, since the connecting rod of the present invention is comprised by a hollow rod. The lighter weight will also contribute to reduce wear on pinned connections.